Hydrolysis of the Organometallic Aqua Ion fac-Triaquatricarbonylrhenium(I). Mechanism, pKa, and Formation Constants of the Polynuclear Hydrolysis Products
A Egli, K Hegetschweiler, R Alberto, U Abram… - …, 1997 - ACS Publications
Organometallics, 1997•ACS Publications
Hydrolytic pathways of the organometallic aqua ion [Re (CO) 3 (H2O) 3]+(2) in aqueous
media were investigated by means of potentiometric titration experiments. The aqua
complex 2 was obtained quantitatively by dissolving (NEt4) 2 [Re (CO) 3Br3](1) in water.
Conventional alkalimetric titrations (0.1 M KNO3, 25° C) allowed the determination of the
formation constants of [Re3 (CO) 9 (μ2-OH) 3 (μ3-OH)]-(3) and [Re2 (CO) 6 (μ2-OH) 3]-(4).
The neutral dinuclear [Re2 (CO) 6 (μ2-OH) 2 (H2O) 2](5) was observed as a minor species …
media were investigated by means of potentiometric titration experiments. The aqua
complex 2 was obtained quantitatively by dissolving (NEt4) 2 [Re (CO) 3Br3](1) in water.
Conventional alkalimetric titrations (0.1 M KNO3, 25° C) allowed the determination of the
formation constants of [Re3 (CO) 9 (μ2-OH) 3 (μ3-OH)]-(3) and [Re2 (CO) 6 (μ2-OH) 3]-(4).
The neutral dinuclear [Re2 (CO) 6 (μ2-OH) 2 (H2O) 2](5) was observed as a minor species …
Hydrolytic pathways of the organometallic aqua ion [Re(CO)3(H2O)3]+ (2) in aqueous media were investigated by means of potentiometric titration experiments. The aqua complex 2 was obtained quantitatively by dissolving (NEt4)2[Re(CO)3Br3] (1) in water. Conventional alkalimetric titrations (0.1 M KNO3, 25 °C) allowed the determination of the formation constants of [Re3(CO)9(μ2-OH)3(μ3-OH)]- (3) and [Re2(CO)6(μ2-OH)3]- (4). The neutral dinuclear [Re2(CO)6(μ2-OH)2(H2O)2] (5) was observed as a minor species. A fast titration technique was used to investigate a rapid preequilibrium, consisting of the formation of the mononuclear deprotonation products [Re(CO)3(OH)(H2O)2] (6) and [Re(CO)3(OH)2(H2O)]- (7). The corresponding pKa values are 7.5(2) and 9.3(3). The immediate extraction of an aqueous solution of 2 with diethyl ether after base addition (1 equiv) led to the quantitative isolation of the well-known cubane cluster [Re(CO)3(OH)]4 (8), which was obtained as a DMF (8b) or OPPh3 adduct (8c). Attempts to isolate the aqua complex 2 as a crystalline material by precipitating the bromo ligands of 1 with AgCF3COO resulted in the formation of (NEt4)2[Re(CO)3(CF3COO)3] (9). The structures of 8b, 8c, and 9 were elucidated by single-crystal X-ray analysis.
ACS Publications以上显示的是最相近的搜索结果。 查看全部搜索结果